Since minor restrictions were imposed a year ago, public nudity has burgeoned in San Francisco, testing residents' famous tolerance. But a ban isn't universally welcomed, either.

George Davis, 65, exercises his right to be nude while reading at the corner… (Maria L. LaGanga, Los Angeles…)

SAN FRANCISCO — A year after passing an ordinance to gently regulate al fresco nudity — requiring that naturists place something between their seats and public seating — city officials are scheduled to vote Tuesday on whether to ban public nakedness outright.

Well, almost outright. This being San Francisco, there are exceptions:

The preschool set still could go diaper-less anywhere and everywhere. Fetishists could drop trou for a flogging during the annual Folsom Street Fair, billed as the world's largest leather fest.

The proposed ban would not stop the athletically inclined from jettisoning their shorts during the Bay to Breakers run — the historic, costume-optional race through this city's microclimates (chilly to chillier). And Dykes on Bikes could wear — or not — whatever they wished during the Pride Parade.

But a starkers stroll down Market Street would most emphatically be out if the prohibition passes.

"In its traditional form in San Francisco, public nudity was fine," said Supervisor Scott Wiener, who represents the Castro District and introduced both ordinances. "It was fine to have a random [naked] person walking through the neighborhood once in a while. It was fine at public festivals and parades."

But although many talk about the tolerant "spirit of San Francisco," Wiener said, "what's happening now is … a caricature."

You can thank the "Naked Guys" for that.

Until recently, officials generally had turned the other cheek to questions of public nudity — particularly when the sightings of sandal-clad men with all-body tans around the Castro district, the heart of gay San Francisco, were sporadic.

Then two years ago, when Jane Warner Plaza was dedicated at the intersection of Castro and Market streets, the number of Naked Guys grew. And so did the complaints, from gay men who live in the area and shop owners near the gathering spot eventually dubbed the "Buff Stop."

Wiener's attempt at regulation last year banned nudity in restaurants and established the outdoor seating guidelines. The goal was to bring a little civility back into the practice of urban nudism. Unfortunately, it had the opposite effect.

The number of nudists grew, Wiener said, and some apparently accessorized the usual shoes and sun hats with jewelry that cannot be described fully in a family newspaper.

Over the summer, Rob Cox, board secretary of the Castro/Eureka Valley Neighborhood Assn., and other community leaders canvassed business owners in the area. They asked how the influx of Naked Guys had affected commerce.

"Ninety percent of the business owners were furious," Cox said. "I had heard it a lot from neighbors too. So we passed that information on" to Wiener.

In early October, the supervisor proposed the stricter ban, calling it legislation "I was hoping that I would never have to introduce." But the Castro, he pointed out, was known for "its diversity and its vibrance," and that sensibility was under attack.

"Jane Warner Plaza is the only usable public plaza in the Castro," he said during the Board of Supervisors meeting. "It is our town square. And it has become dominated just about every afternoon by one group.... The Castro is not about a group of men exposing themselves every day."

Last week, the naturists struck back.

First, they held a nude-in on the steps of City Hall. Then they filed a federal lawsuit.

To Gypsy Taub, protest organizer and hostess of a local show called "My Naked Truth TV," the proposed ban is proof that officials want to turn the city back into "the Dark Ages of body shame and fear."

To Taub's 9-year-old son, Bunny Gonzalez, who was fully clothed during the protest, nudity "is a good cause. Scott Wiener is trying to make nudity bad."

Placard-waving Web designer Mitch Hightower said the San Francisco clampdown smacked of gentrification: "More and more they're taking away the things that are only-in-San Francisco." Dressed in a T-shirt, sun hat and not much else, even he had to admit: "I'm cold!"

Ckiara Rose, in ballet-style flats and chandelier earrings, said banning public nudity in the city was pure hypocrisy. "San Francisco was founded on the Barbary Coast, full of brothels and saloons," the self-proclaimed sex worker said. "They don't come from Puritan origins."

But that's the way things could be headed if Wiener and his colleagues aren't stopped, said attorney Christina (formerly Christopher) DiEdoardo, who is representing Taub, Hightower and others in the federal lawsuit.

Gripping the legal document in her hand before marching on the federal building, DiEdoardo declared to the variously clad group, "What a gorgeous day for a rally in San Francisco … and for us to return to real San Francisco values!"

And how was DiEdoardo dressed on a breezy autumn afternoon as she struck a blow for the 1st Amendment rights of the naked? She wore a brightly flowered blouse and black slacks.